//
// Created by Administrator on 2020/2/22 0022.
//

#include <cstring>
#include <malloc.h>
#include "utils.h"

//将char类型转换成jstring类型
jstring cstr2jstring(JNIEnv *env, const char *pat) {
    // 定义java String类 strClass
    jclass strClass = (env)->FindClass("Ljava/lang/String;");
    // 获取java String类方法String(byte[],String)的构造器,用于将本地byte[]数组转换为一个新String
    jmethodID ctorID = (env)->GetMethodID(strClass, "<init>", "([BLjava/lang/String;)V");
    // 建立byte数组
    jbyteArray bytes = (env)->NewByteArray((jsize) strlen(pat));
    // 将char* 转换为byte数组
    (env)->SetByteArrayRegion(bytes, 0, (jsize) strlen(pat), (jbyte *) pat);
    //设置String, 保存语言类型,用于byte数组转换至String时的参数
    jstring encoding = (env)->NewStringUTF("UTF-8");
    //将byte数组转换为java String,并输出
    return (jstring) (env)->NewObject(strClass, ctorID, bytes, encoding);

}

char *jstring2cstr(JNIEnv *env, jstring jstr) {
    char *rtn = NULL;
    jclass clsstring = env->FindClass("java/lang/String");
    jstring strencode = env->NewStringUTF("UTF-8");
    jmethodID mid = env->GetMethodID(clsstring, "getBytes", "(Ljava/lang/String;)[B");
    jbyteArray barr = (jbyteArray) env->CallObjectMethod(jstr, mid, strencode);
    jsize alen = env->GetArrayLength(barr);
    jbyte *ba = env->GetByteArrayElements(barr, JNI_FALSE);
    if (alen > 0) {
        rtn = (char *) malloc(alen + 1); //new char[alen+1];
        memcpy(rtn, ba, alen);
        rtn[alen] = 0;
    }
    env->ReleaseByteArrayElements(barr, ba, 0);

    return rtn;
}